Wavelength division multiplexing (WDM) has enabled telecommunication service providers to fully exploit the transmission capacity of optical fibers in their core network. State of the art systems in long-haul networks now have aggregated capacities of terabits per second. Moreover, by providing multiple independent multi-gigabit channels, WDM technologies offer service providers with a straight forward way to build networks and expand networks to support multiple clients with different requirements. At the same time these technologies have evolved from long haul networks down to the access networks as well as into data centers, to support the continuing inexorable demand for data. In order to reduce costs, enhance network flexibility, reduce spares, and provide reconfigurability many service providers have migrated away from fixed wavelength transmitters, receivers, and transceivers, to wavelength tunable transmitters, receivers, and transceivers as well as wavelength dependent add-drop multiplexers, space switches etc. However, to meet the competing demands for improved performance, increased integration, reduced footprint, reduced power consumption, increased flexibility, reconfigurability, and lower cost the prior art solutions using discrete components must be superseded. Accordingly, within the technologies to exploit/adopt are monolithic optical circuit technologies, hybrid optoelectronic integration, microelectromechanical systems (MEMS), and microoptoelectromechanical systems (MOEMS).
An essential MOEMS element in a WDM system is a MOEMS mirror or waveguide capable of deflection under electronic control. However, unlike most MEMS device configurations where the MEMS is simply used to switch between positions, when the MEMS includes an optical waveguide, the state of MOEMS becomes important in all transition positions. The characteristics of the MEMS determines the characteristics of the WDM system in that it affects the number of wavelength channels and the dynamic wavelength switching capabilities of the system. The role of the MEMS becomes essential in an integrated photonic device such as it is responsible not only for altering the paths of light but directing light through a plurality of wavelength filters which allows the reflection or transmission of a dedicated, mono-chromatic light.
Accordingly, it would be beneficial to improve the performance of such MEMS and thereby the performance of the optical components and optical systems they form part of. Beneficially, the inventors have established a range of improvements to the design and implementation of such MOEMS mirrors and MOEMS waveguides as well as optical waveguide technologies supporting the extension of these device concepts in datacom, telecom, sensors, optical delay lines, and mid-infrared optical spectroscopy for example.
Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.